Remedial System Operating Successfully; Additional Source Area Discovered

The Air Sparging/Soil Vapor Extraction (AS/SVE) System at the site has been 
in operation in the northern portion of  the site for approximately eleven months.  The consultant for the site, ECSMarin of Richmond, Vermont estimates that approximately 327 pounds, or 54 gallons of gasoline have been removed by the AS/SVE system from the former gasoline underground storage tank area since the system began operation in August of 2002. 

area did not seem to be falling as predicted.   A series of subsurface soil borings were drilled on May 21 to try and determine the cause.  The contractor discovered an underground steel culvert near the entrance to the site.  It appears that over the years since the original release petroleum has migrated in the subsurface and accumulated in and around this culvert.  It now serves as an additional source of groundwater contamination.   Additional subsurface investigation is planned for August to determine the extent of this additional source area, with the goal of developing a plan to address it and allow the cleanup to continue.

Groundwater samples were also collected from the site monitoring wells on May 21.  The results were consistent with the December 2002 monitoring round, showing decreased contaminant concentrations in the AS/SVE treatment area; and concentrations consistent with historical levels in the downgradient wells.

In the southern portion of the site, samples from monitoring wells located near the former drywell that was removed in 2002 continued to contain very low levels of contaminants.  These levels are below the cleanup standards for groundwater. However, monitoring 
of these wells will continue, with the hope that contaminant concentrations will fall to non-detectable levels. 

ECSMarin personnel will continue to visit the site regularly to perform maintenance activities and to collect data and samples in Area I that will allow the effectiveness of the AS/SVE system to be evaluated.